The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
As continuous demand for an improvement of fuel efficiency of a vehicle as well as strict regulations on exhaust gas of each country increases desire for an environmentally-friendly vehicle. As a realistic alternative, a hybrid electric vehicle (HEV) is proposed.
The HEV is one classification of an electric vehicle including a pure electric vehicle (EV), which uses an electric motor as power, and a fuel cell electric vehicle (FCEV), and is distinguished from other electric vehicles in that the HEV receives power from two or more kinds of power sources including a driving motor and an engine. In the present disclosure, the HEV means a vehicle driven by two or more power sources including the driving motor and the engine, and includes a plug-in hybrid electric vehicle (PHEV) in a broad sense.
In the HEV, an engine clutch is mounted between the engine and the driving motor in order to transmit power of the engine to a driving shaft. The HEV provides an operation in an EV mode, in which the HEV travels only with a driving motor torque, and a HEV mode, in which the HEV travels with a sum of an engine torque and a driving motor torque, according to a connection of the engine clutch.
A transmission mounted electric device (TMED) scheme and a flywheel mounted electric device (FMED) scheme, in which an automatic transmission (AT) or a dual clutch transmission (DCT) is mounted, may be applied to the HEV.
The HEV in the TMED scheme includes two motors, and a speed of a motor connected with an engine is measured, and then vibration of the engine is extracted.
In the related art, when a vibrational component of the engine is extracted, a filter of a target frequency single band desired to be decreased is used. However, concerning the characteristic of a filter response, when an engine vibration frequency is changed based on a change in an engine speed, a size and a phase of the extracted vibrational component may be changed. Due to this, there is a limitation when attempting to decrease vibration.